The present invention relates to a decorative bar or rail formed of a natural stone rod combined with a metal armature or bracketed structure which is configured to be mounted on a wall surface of a room or a floor surface of a building to provide an attractive and useful holder or railing.
For example, the stone and metal bar may be installed on the wall of a bathroom for use as a towel holder or a hand support; it may be installed on a door as a door pull; it may be installed in a closet for use as a rod on which to hang clothes; or it may be mounted on vertical supports on the side of a staircase to serve as a hand or guard rail or as the cap on a railing at a balcony edge. In general, the present invention is intended to add an attractive architectural accent in any situation where a bar or railing is provided in a building.
The use of stone for architectural purposes is known throughout history. Large vertical columns have graced the facades of buildings since early Greco-Roman times. Natural stone is a durable and attractive building material but its use has been limited by its lack of tensile strength. When used in compression, as in vertical stone columns for example, the stone is capable of bearing enormous loads. However, when a lateral force is applied that causes internal tension, for example when weight is applied to the center of a horizontal stone beam, the stone has a tendency to crack. For this reason metals and plastics have long since replaced stone as the materials of choice for architectural purposes where a tensile force is present or expected.
It is known from the Chinese Patent No. 2857765Y to reinforce a bar made of stone by means of an internal metal rod. The disclosed bar is intended for use in a bathroom, for example as a towel bar or shower curtain rod. A cylindrical metal rod is somehow embedded in the center of a stone bar, which may be round or square in cross-section, presumably by drilling a round hole along the longitudinal central axis of the stone. Once reinforced in this way, the bar can be placed in use horizontally presumably by supporting it at both ends in a manner that is not defined or explained.
The Chinese Patent No. 201284914Y discloses an improvement in this prior art stone bar which avoids drilling a long hole through the center of the bar. This reference teaches the reinforcement of stone curtain rods, towel racks and the like by inserting a metal rod in a longitudinal notch or groove on one or more sides of the bar and affixing the rod(s) to the stone by means of an adhesive. The metal rod can be round, square or even triangular in cross-section. It can fill a groove in the stone bar or be covered by a separate, filler material that fills the remainder of the groove. Once inserted, however, the metal rod fulfills no other purpose than to reinforce the stone bar. As in the case with the Chinese Patent No. 2857765Y, this metal rod is substantially hidden from view.
These two prior art references, taken together, teach how natural stone bars may be reinforced. However, the reinforced stone bars, so constructed, must be held by some type of supporting fixture when installed in a bathroom or the like. This supporting fixture must presumably grip or clamp the outer surface of the stone which, being brittle, is subject to damage, either upon installation or during use. Because this configuration as not robust, such stone bars may be considered impractical for architectural use. Furthermore, these references teach making substantial cuts or openings in the stone bars for insertion of the reinforcing metal rods.
The Chinese Patent No. 2857765Y shows that the diameter of the metal rod is approximately one-third the diameter or width of the stone bar. It would be exceedingly difficult to drill a longitudinal hole through a stone rod from one end to the other. The Chinese Patent No. 201284914Y discloses various types of stone bars with various configurations of longitudinal grooves for insertion of the metal rods. In each embodiment shown, the groove is approximately one quarter of the width of the stone bar. In all cases where a round or square metal rod is embedded in a stone bar for reinforcement, this rod must have sufficient thickness to withstand any bending stresses that are anticipated. The substantial cuts in the stone, for the purposed of reinforcement, result in a weakened stone structure which is naturally fragile and brittle and therefore subject to breakage.